Hmmm, it's not working for the Obout:textbox.

Here is how I have the textbox control and button control in place:

<obout:OboutButton ID="ZipButton" runat="server" Text="Download as Zip" Width="150px"
                CausesValidation="true" OnClick="ZipButton_Click" OnClientClick="return validate();">
            </obout:OboutButton>
            &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
            <asp:Label ID="PasswordLabel" runat="server" Text="Zip File Password:" ForeColor="Black"
                Font-Bold="true"></asp:Label>&nbsp;&nbsp;
            <obout:OboutTextBox ID="ZipPwdTextBox" runat="server"></obout:OboutTextBox>